netsock2.c

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/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 2010, Digium, Inc.
 *
 * Viagénie <asteriskv6@viagenie.ca>
 *
 * See http://www.asterisk.org for more information about
 * the Asterisk project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2. See the LICENSE file
 * at the top of the source tree.
 */
 
/*! \file
 *
 * \brief Network socket handling
 *
 * \author Viagénie <asteriskv6@viagenie.ca>
 */
 
/*** MODULEINFO
    <support_level>core</support_level>
 ***/
 
#include "asterisk.h"
 
#include "asterisk/config.h"
#include "asterisk/netsock2.h"
#include "asterisk/utils.h"
#include "asterisk/threadstorage.h"
 
int ast_sockaddr_ipv4_mapped(const struct ast_sockaddr *addr, struct ast_sockaddr *ast_mapped)
{
    const struct sockaddr_in6 *sin6;
    struct sockaddr_in sin4;
 
    if (!ast_sockaddr_is_ipv6(addr)) {
        return 0;
    }
 
    if (!ast_sockaddr_is_ipv4_mapped(addr)) {
        return 0;
    }
 
    sin6 = (const struct sockaddr_in6*)&addr->ss;
 
    memset(&sin4, 0, sizeof(sin4));
    sin4.sin_family = AF_INET;
    sin4.sin_port = sin6->sin6_port;
    sin4.sin_addr.s_addr = ((uint32_t *)&sin6->sin6_addr)[3];
 
    ast_sockaddr_from_sin(ast_mapped, &sin4);
 
    return 1;
}
 
 
AST_THREADSTORAGE(ast_sockaddr_stringify_buf);
 
char *ast_sockaddr_stringify_fmt(const struct ast_sockaddr *sa, int format)
{
    struct ast_sockaddr sa_ipv4;
    const struct ast_sockaddr *sa_tmp;
    char host[NI_MAXHOST];
    char port[NI_MAXSERV];
    struct ast_str *str;
    int e;
    static const size_t size = sizeof(host) - 1 + sizeof(port) - 1 + 4;
 
 
    if (ast_sockaddr_isnull(sa)) {
        return "(null)";
    }
 
    if (!(str = ast_str_thread_get(&ast_sockaddr_stringify_buf, size))) {
        return "";
    }
 
    if (ast_sockaddr_ipv4_mapped(sa, &sa_ipv4)) {
        sa_tmp = &sa_ipv4;
    } else {
        sa_tmp = sa;
    }
 
    if ((e = getnameinfo((struct sockaddr *)&sa_tmp->ss, sa_tmp->len,
                 format & AST_SOCKADDR_STR_ADDR ? host : NULL,
                 format & AST_SOCKADDR_STR_ADDR ? sizeof(host) : 0,
                 format & AST_SOCKADDR_STR_PORT ? port : 0,
                 format & AST_SOCKADDR_STR_PORT ? sizeof(port): 0,
                 NI_NUMERICHOST | NI_NUMERICSERV))) {
        ast_log(LOG_ERROR, "getnameinfo(): %s\n", gai_strerror(e));
        return "";
    }
 
    if ((format & AST_SOCKADDR_STR_REMOTE) == AST_SOCKADDR_STR_REMOTE) {
        char *p;
        if (ast_sockaddr_is_ipv6_link_local(sa) && (p = strchr(host, '%'))) {
            *p = '\0';
        }
    }
 
    switch ((format & AST_SOCKADDR_STR_FORMAT_MASK))  {
    case AST_SOCKADDR_STR_DEFAULT:
        ast_str_set(&str, 0, sa_tmp->ss.ss_family == AF_INET6 ?
                "[%s]:%s" : "%s:%s", host, port);
        break;
    case AST_SOCKADDR_STR_ADDR:
        ast_str_set(&str, 0, "%s", host);
        break;
    case AST_SOCKADDR_STR_HOST:
        ast_str_set(&str, 0,
                sa_tmp->ss.ss_family == AF_INET6 ? "[%s]" : "%s", host);
        break;
    case AST_SOCKADDR_STR_PORT:
        ast_str_set(&str, 0, "%s", port);
        break;
    default:
        ast_log(LOG_ERROR, "Invalid format\n");
        return "";
    }
 
    return ast_str_buffer(str);
}
 
int ast_sockaddr_cidr_bits(const struct ast_sockaddr *sa)
{
    struct ast_sockaddr sa_ipv4;
    const struct ast_sockaddr *sa_tmp;
    int bits = 0;
    int bytes;
    int i;
    int j;
    char *addr;
 
    if (ast_sockaddr_isnull(sa)) {
        return 0;
    }
 
    if (ast_sockaddr_ipv4_mapped(sa, &sa_ipv4)) {
        sa_tmp = &sa_ipv4;
    } else {
        sa_tmp = sa;
    }
 
    bytes = sa_tmp->len;
    addr = ((struct sockaddr *)&sa_tmp->ss)->sa_data;
 
    for (i = 0; i < bytes ; ++i) {
        for (j = 0; j < 8; ++j) {
            if ((addr[i] >> j) & 1) {
                bits++;
            }
        }
    }
 
    return bits;
}
 
int ast_sockaddr_split_hostport(char *str, char **host, char **port, int flags)
{
    char *s = str;
    char *orig_str = str;/* Original string in case the port presence is incorrect. */
    char *host_end = NULL;/* Delay terminating the host in case the port presence is incorrect. */
 
    ast_debug(5, "Splitting '%s' into...\n", str);
    *host = NULL;
    *port = NULL;
    if (*s == '[') {
        *host = ++s;
        for (; *s && *s != ']'; ++s) {
        }
        if (*s == ']') {
            host_end = s;
            ++s;
        }
        if (*s == ':') {
            *port = s + 1;
        }
    } else {
        *host = s;
        for (; *s; ++s) {
            if (*s == ':') {
                if (*port) {
                    *port = NULL;
                    break;
                } else {
                    *port = s;
                }
            }
        }
        if (*port) {
            host_end = *port;
            ++*port;
        }
    }
 
    switch (flags & PARSE_PORT_MASK) {
    case PARSE_PORT_IGNORE:
        *port = NULL;
        break;
    case PARSE_PORT_REQUIRE:
        if (*port == NULL) {
            ast_log(LOG_WARNING, "Port missing in %s\n", orig_str);
            return 0;
        }
        break;
    case PARSE_PORT_FORBID:
        if (*port != NULL) {
            ast_log(LOG_WARNING, "Port disallowed in %s\n", orig_str);
            return 0;
        }
        break;
    }
 
    /* Can terminate the host string now if needed. */
    if (host_end) {
        *host_end = '\0';
    }
    ast_debug(5, "...host '%s' and port '%s'.\n", *host, *port ? *port : "");
    return 1;
}
 
 
 
int ast_sockaddr_parse(struct ast_sockaddr *addr, const char *str, int flags)
{
    struct addrinfo hints;
    struct addrinfo *res;
    char *s;
    char *host;
    char *port;
    int e;
 
    s = ast_strdupa(str);
    if (!ast_sockaddr_split_hostport(s, &host, &port, flags)) {
        return 0;
    }
 
    memset(&hints, 0, sizeof(hints));
    /* Hint to get only one entry from getaddrinfo */
    hints.ai_socktype = SOCK_DGRAM;
 
#ifdef AI_NUMERICSERV
    hints.ai_flags = AI_NUMERICHOST | AI_NUMERICSERV;
#else
    hints.ai_flags = AI_NUMERICHOST;
#endif
    if ((e = getaddrinfo(host, port, &hints, &res))) {
        if (e != EAI_NONAME) { /* if this was just a host name rather than a ip address, don't print error */
            ast_log(LOG_ERROR, "getaddrinfo(\"%s\", \"%s\", ...): %s\n",
                host, S_OR(port, "(null)"), gai_strerror(e));
        }
        return 0;
    }
 
    /*
     * I don't see how this could be possible since we're not resolving host
     * names. But let's be careful...
     */
    if (res->ai_next != NULL) {
        ast_log(LOG_WARNING, "getaddrinfo() returned multiple "
            "addresses. Ignoring all but the first.\n");
    }
 
    if (addr) {
        addr->len = res->ai_addrlen;
        memcpy(&addr->ss, res->ai_addr, addr->len);
    }
 
    freeaddrinfo(res);
 
    return 1;
}
 
int ast_sockaddr_resolve(struct ast_sockaddr **addrs, const char *str,
             int flags, int family)
{
    struct addrinfo hints, *res, *ai;
    char *s, *host, *port;
    int e, i, res_cnt;
 
    if (!str) {
        *addrs = NULL;
        return 0;
    }
 
    s = ast_strdupa(str);
    if (!ast_sockaddr_split_hostport(s, &host, &port, flags)) {
        *addrs = NULL;
        return 0;
    }
 
    memset(&hints, 0, sizeof(hints));
    hints.ai_family = family;
    hints.ai_socktype = SOCK_DGRAM;
 
    if ((e = getaddrinfo(host, port, &hints, &res))) {
        ast_log(LOG_ERROR, "getaddrinfo(\"%s\", \"%s\", ...): %s\n",
            host, S_OR(port, "(null)"), gai_strerror(e));
        *addrs = NULL;
        return 0;
    }
 
    res_cnt = 0;
    for (ai = res; ai; ai = ai->ai_next) {
        res_cnt++;
    }
 
    if (res_cnt == 0) {
        *addrs = NULL;
        goto cleanup;
    }
 
    if ((*addrs = ast_malloc(res_cnt * sizeof(struct ast_sockaddr))) == NULL) {
        res_cnt = 0;
        goto cleanup;
    }
 
    i = 0;
    for (ai = res; ai; ai = ai->ai_next) {
        (*addrs)[i].len = ai->ai_addrlen;
        memcpy(&(*addrs)[i].ss, ai->ai_addr, ai->ai_addrlen);
        ++i;
    }
 
cleanup:
    freeaddrinfo(res);
    return res_cnt;
}
 
/*! \brief Pulls first resolved address and returns it */
int ast_sockaddr_resolve_first_af(struct ast_sockaddr *addr,
                      const char* name, int flag, int family)
{
    struct ast_sockaddr *addrs;
    int addrs_cnt;
 
    addrs_cnt = ast_sockaddr_resolve(&addrs, name, flag, family);
    if (addrs_cnt <= 0) {
        return 1;
    }
    if (addrs_cnt > 1) {
        ast_debug(1, "Multiple addresses resolving %s, using the first one only\n", name);
    }
 
    ast_sockaddr_copy(addr, &addrs[0]);
 
    ast_free(addrs);
    return 0;
}
 
int ast_sockaddr_apply_netmask(const struct ast_sockaddr *addr, const struct ast_sockaddr *netmask,
        struct ast_sockaddr *result)
{
    int res = 0;
 
    if (ast_sockaddr_is_ipv4(addr)) {
        struct sockaddr_in result4 = { 0, };
        struct sockaddr_in *addr4 = (struct sockaddr_in *) &addr->ss;
        struct sockaddr_in *mask4 = (struct sockaddr_in *) &netmask->ss;
        result4.sin_family = AF_INET;
        result4.sin_addr.s_addr = addr4->sin_addr.s_addr & mask4->sin_addr.s_addr;
        ast_sockaddr_from_sin(result, &result4);
    } else if (ast_sockaddr_is_ipv6(addr)) {
        struct sockaddr_in6 result6 = { 0, };
        struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *) &addr->ss;
        struct sockaddr_in6 *mask6 = (struct sockaddr_in6 *) &netmask->ss;
        int i;
        result6.sin6_family = AF_INET6;
        for (i = 0; i < 4; ++i) {
            V6_WORD(&result6, i) = V6_WORD(addr6, i) & V6_WORD(mask6, i);
        }
        memcpy(&result->ss, &result6, sizeof(result6));
        result->len = sizeof(result6);
    } else {
        /* Unsupported address scheme */
        res = -1;
    }
 
    return res;
}
 
int ast_sockaddr_cmp(const struct ast_sockaddr *a, const struct ast_sockaddr *b)
{
    const struct ast_sockaddr *a_tmp, *b_tmp;
    struct ast_sockaddr ipv4_mapped;
 
    a_tmp = a;
    b_tmp = b;
 
    if (a_tmp->len != b_tmp->len) {
        if (ast_sockaddr_ipv4_mapped(a, &ipv4_mapped)) {
            a_tmp = &ipv4_mapped;
        } else if (ast_sockaddr_ipv4_mapped(b, &ipv4_mapped)) {
            b_tmp = &ipv4_mapped;
        }
    }
 
    if (a_tmp->len < b_tmp->len) {
        return -1;
    } else if (a_tmp->len > b_tmp->len) {
        return 1;
    }
 
    return memcmp(&a_tmp->ss, &b_tmp->ss, a_tmp->len);
}
 
int ast_sockaddr_cmp_addr(const struct ast_sockaddr *a, const struct ast_sockaddr *b)
{
    const struct ast_sockaddr *a_tmp, *b_tmp;
    struct ast_sockaddr ipv4_mapped;
    const struct in_addr *ip4a, *ip4b;
    const struct in6_addr *ip6a, *ip6b;
    int ret = -1;
 
    a_tmp = a;
    b_tmp = b;
 
    if (a_tmp->len != b_tmp->len) {
        if (ast_sockaddr_ipv4_mapped(a, &ipv4_mapped)) {
            a_tmp = &ipv4_mapped;
        } else if (ast_sockaddr_ipv4_mapped(b, &ipv4_mapped)) {
            b_tmp = &ipv4_mapped;
        }
    }
 
    if (a->len < b->len) {
        ret = -1;
    } else if (a->len > b->len) {
        ret = 1;
    }
 
    switch (a_tmp->ss.ss_family) {
    case AF_INET:
        ip4a = &((const struct sockaddr_in*)&a_tmp->ss)->sin_addr;
        ip4b = &((const struct sockaddr_in*)&b_tmp->ss)->sin_addr;
        ret = memcmp(ip4a, ip4b, sizeof(*ip4a));
        break;
    case AF_INET6:
        ip6a = &((const struct sockaddr_in6*)&a_tmp->ss)->sin6_addr;
        ip6b = &((const struct sockaddr_in6*)&b_tmp->ss)->sin6_addr;
        ret = memcmp(ip6a, ip6b, sizeof(*ip6a));
        break;
    }
    return ret;
}
 
uint16_t _ast_sockaddr_port(const struct ast_sockaddr *addr, const char *file, int line, const char *func)
{
    /*
     * Test addr->len first to be tolerant of an ast_sockaddr_setnull()
     * addr.  In that case addr->len might be the only value initialized.
     */
    if (addr->len == sizeof(struct sockaddr_in)
        && addr->ss.ss_family == AF_INET) {
        return ntohs(((struct sockaddr_in *)&addr->ss)->sin_port);
    }
    if (addr->len == sizeof(struct sockaddr_in6)
        && addr->ss.ss_family == AF_INET6) {
        return ntohs(((struct sockaddr_in6 *)&addr->ss)->sin6_port);
    }
    if (DEBUG_ATLEAST(1)) {
        ast_log(__LOG_DEBUG, file, line, func, "Not an IPv4 nor IPv6 address, cannot get port.\n");
    }
    return 0;
}
 
void _ast_sockaddr_set_port(struct ast_sockaddr *addr, uint16_t port, const char *file, int line, const char *func)
{
    /*
     * Test addr->len first to be tolerant of an ast_sockaddr_setnull()
     * addr.  In that case addr->len might be the only value initialized.
     */
    if (addr->len == sizeof(struct sockaddr_in)
        && addr->ss.ss_family == AF_INET) {
        ((struct sockaddr_in *)&addr->ss)->sin_port = htons(port);
    } else if (addr->len == sizeof(struct sockaddr_in6)
        && addr->ss.ss_family == AF_INET6) {
        ((struct sockaddr_in6 *)&addr->ss)->sin6_port = htons(port);
    } else if (DEBUG_ATLEAST(1)) {
        ast_log(__LOG_DEBUG, file, line, func,
            "Not an IPv4 nor IPv6 address, cannot set port.\n");
    }
}
 
uint32_t ast_sockaddr_ipv4(const struct ast_sockaddr *addr)
{
    const struct sockaddr_in *sin = (struct sockaddr_in *)&addr->ss;
    return ntohl(sin->sin_addr.s_addr);
}
 
int ast_sockaddr_is_ipv4(const struct ast_sockaddr *addr)
{
    /*
     * Test addr->len first to be tolerant of an ast_sockaddr_setnull()
     * addr.  In that case addr->len might be the only value initialized.
     */
    return addr->len == sizeof(struct sockaddr_in)
        && addr->ss.ss_family == AF_INET;
}
 
int ast_sockaddr_is_ipv4_mapped(const struct ast_sockaddr *addr)
{
    const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&addr->ss;
    return addr->len && IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr);
}
 
int ast_sockaddr_is_ipv4_multicast(const struct ast_sockaddr *addr)
{
    return ((ast_sockaddr_ipv4(addr) & 0xf0000000) == 0xe0000000);
}
 
int ast_sockaddr_is_ipv6_link_local(const struct ast_sockaddr *addr)
{
    const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&addr->ss;
    return ast_sockaddr_is_ipv6(addr) && IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr);
}
 
int ast_sockaddr_is_ipv6(const struct ast_sockaddr *addr)
{
    /*
     * Test addr->len first to be tolerant of an ast_sockaddr_setnull()
     * addr.  In that case addr->len might be the only value initialized.
     */
    return addr->len == sizeof(struct sockaddr_in6)
        && addr->ss.ss_family == AF_INET6;
}
 
int ast_sockaddr_is_any(const struct ast_sockaddr *addr)
{
    union {
        struct sockaddr_storage ss;
        struct sockaddr_in sin;
        struct sockaddr_in6 sin6;
    } tmp_addr = {
        .ss = addr->ss,
    };
 
    return (ast_sockaddr_is_ipv4(addr) && (tmp_addr.sin.sin_addr.s_addr == INADDR_ANY)) ||
        (ast_sockaddr_is_ipv6(addr) && IN6_IS_ADDR_UNSPECIFIED(&tmp_addr.sin6.sin6_addr));
}
 
int ast_sockaddr_hash(const struct ast_sockaddr *addr)
{
    /*
     * For IPv4, return the IP address as-is. For IPv6, return the last 32
     * bits.
     */
    switch (addr->ss.ss_family) {
    case AF_INET:
        return ((const struct sockaddr_in *)&addr->ss)->sin_addr.s_addr;
    case AF_INET6:
        return ((uint32_t *)&((const struct sockaddr_in6 *)&addr->ss)->sin6_addr)[3];
    default:
        ast_log(LOG_ERROR, "Unknown address family '%d'.\n",
            addr->ss.ss_family);
        return 0;
    }
}
 
const char *ast_transport2str(enum ast_transport transport)
{
    switch (transport) {
    case AST_TRANSPORT_TLS:
        return "TLS";
    case AST_TRANSPORT_UDP:
        return "UDP";
    case AST_TRANSPORT_TCP:
        return "TCP";
    case AST_TRANSPORT_WS:
        return "WS";
    case AST_TRANSPORT_WSS:
        return "WSS";
    }
 
    return "Undefined";
}
 
int ast_accept(int sockfd, struct ast_sockaddr *addr)
{
    addr->len = sizeof(addr->ss);
    return accept(sockfd, (struct sockaddr *)&addr->ss, &addr->len);
}
 
int ast_bind(int sockfd, const struct ast_sockaddr *addr)
{
    return bind(sockfd, (const struct sockaddr *)&addr->ss, addr->len);
}
 
int ast_connect(int sockfd, const struct ast_sockaddr *addr)
{
    return connect(sockfd, (const struct sockaddr *)&addr->ss, addr->len);
}
 
int ast_getsockname(int sockfd, struct ast_sockaddr *addr)
{
    addr->len = sizeof(addr->ss);
    return getsockname(sockfd, (struct sockaddr *)&addr->ss, &addr->len);
}
 
ssize_t ast_recvfrom(int sockfd, void *buf, size_t len, int flags,
             struct ast_sockaddr *src_addr)
{
    src_addr->len = sizeof(src_addr->ss);
    return recvfrom(sockfd, buf, len, flags,
            (struct sockaddr *)&src_addr->ss, &src_addr->len);
}
 
ssize_t ast_sendto(int sockfd, const void *buf, size_t len, int flags,
           const struct ast_sockaddr *dest_addr)
{
    return sendto(sockfd, buf, len, flags,
              (const struct sockaddr *)&dest_addr->ss, dest_addr->len);
}
 
int ast_set_qos(int sockfd, int tos, int cos, const char *desc)
{
    int res = 0;
    int set_tos;
    int set_tclass;
    struct ast_sockaddr addr;
 
    /* If the sock address is IPv6, the TCLASS field must be set. */
    set_tclass = !ast_getsockname(sockfd, &addr) && ast_sockaddr_is_ipv6(&addr) ? 1 : 0;
 
    /* If the sock address is IPv4 or (IPv6 set to any address [::]) set TOS bits */
    set_tos = (!set_tclass || (set_tclass && ast_sockaddr_is_any(&addr))) ? 1 : 0;
 
    if (set_tos) {
        if ((res = setsockopt(sockfd, IPPROTO_IP, IP_TOS, &tos, sizeof(tos)))) {
            ast_log(LOG_WARNING, "Unable to set %s DSCP TOS value to %d (may be you have no "
                "root privileges): %s\n", desc, tos, strerror(errno));
        } else if (tos) {
            ast_verb(2, "Using %s TOS bits %d\n", desc, tos);
        }
    }
 
#if defined(IPV6_TCLASS) && defined(IPPROTO_IPV6)
    if (set_tclass) {
        if (!ast_getsockname(sockfd, &addr) && ast_sockaddr_is_ipv6(&addr)) {
            if ((res = setsockopt(sockfd, IPPROTO_IPV6, IPV6_TCLASS, &tos, sizeof(tos)))) {
                ast_log(LOG_WARNING, "Unable to set %s DSCP TCLASS field to %d (may be you have no "
                    "root privileges): %s\n", desc, tos, strerror(errno));
            } else if (tos) {
                ast_verb(2, "Using %s TOS bits %d in TCLASS field.\n", desc, tos);
            }
        }
    }
#endif
 
#ifdef linux
    if (setsockopt(sockfd, SOL_SOCKET, SO_PRIORITY, &cos, sizeof(cos))) {
        ast_log(LOG_WARNING, "Unable to set %s CoS to %d: %s\n", desc, cos,
            strerror(errno));
    } else if (cos) {
        ast_verb(2, "Using %s CoS mark %d\n", desc, cos);
    }
#endif
 
    return res;
}
 
int _ast_sockaddr_to_sin(const struct ast_sockaddr *addr,
            struct sockaddr_in *sin, const char *file, int line, const char *func)
{
    if (ast_sockaddr_isnull(addr)) {
        memset(sin, 0, sizeof(*sin));
        return 1;
    }
 
    if (addr->len != sizeof(*sin)) {
        ast_log(__LOG_ERROR, file, line, func, "Bad address cast to IPv4\n");
        return 0;
    }
 
    if (addr->ss.ss_family != AF_INET && DEBUG_ATLEAST(1)) {
        ast_log(__LOG_DEBUG, file, line, func, "Address family is not AF_INET\n");
    }
 
    *sin = *(struct sockaddr_in *)&addr->ss;
    return 1;
}
 
void _ast_sockaddr_from_sin(struct ast_sockaddr *addr, const struct sockaddr_in *sin,
        const char *file, int line, const char *func)
{
    memcpy(&addr->ss, sin, sizeof(*sin));
 
    if (addr->ss.ss_family != AF_INET && DEBUG_ATLEAST(1)) {
        ast_log(__LOG_DEBUG, file, line, func, "Address family is not AF_INET\n");
    }
 
    addr->len = sizeof(*sin);
}